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URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 149

NWS STORM PREDICTION CENTER NORMAN OK

615 PM CDT THU APR 5 2012



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       CENTRAL AND EASTERN ALABAMA



EFFECTIVE THIS THURSDAY NIGHT FROM 615 PM UNTIL MIDNIGHT CDT.



HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 55

STATUTE MILES EAST AND WEST OF A LINE FROM 20 MILES WEST

NORTHWEST OF GADSDEN ALABAMA TO 30 MILES EAST SOUTHEAST OF

MONTGOMERY ALABAMA.  FOR A COMPLETE DEPICTION OF THE WATCH SEE

THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU9).



REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE

FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH

AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR

THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS

AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY

DO PRODUCE TORNADOES.



OTHER WATCH INFORMATION...CONTINUE...WW 146...WW 147...WW 148...



DISCUSSION...STORMS HAVE INCREASED IN BOTH COVERAGE AND INTENSITY AS

COMPACT MID/UPPER LOW AND ASSOCIATED VORT CENTER DEVELOP SEWD ACROSS

TN VALLEY THIS EVENING. STEEPENING MID-LEVEL LAPSE RATES AND

STRENGTHENING FLOW FIELDS....IN CONCERT WITH ENHANCED DPVA SHOULD

COMPENSATE FOR LACK OF STRONGER CONVECTIVE INSTABILITY TO SUSTAIN A

FEW STOUT UPDRAFTS MOSTLY CAPABLE OF LARGE HAIL. SOME TENDENCY

TOWARD SMALL-SCALE LINEAR DEVELOPMENT ALSO SUGGESTS SOME INCREASE IN

LOCALLY STRONG WINDS AS CONVECTION BECOMES PREFERENTIALLY ALIGNED

WITH 65KT MID LEVEL JET STREAK MOVING INTO THE AREA.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 350. MEAN STORM

MOTION VECTOR 27030.





...CARBIN

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